calling super() causes __class__ to be not defined when sys.settrace(trace) is set

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2019-04-11.17:18:57.188>
labels = ['interpreter-core', 'type-bug', '3.8']
title = 'calling super() causes __class__ to be not defined when sys.settrace(trace) is set'
updated_at = <Date 2019-04-11.17:18:57.188>
user = 'https://github.com/tirkarthi'

bugs.python.org fields:

activity = <Date 2019-04-11.17:18:57.188>
actor = 'xtreak'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Interpreter Core']
creation = <Date 2019-04-11.17:18:57.188>
creator = 'xtreak'
dependencies = []
files = []
hgrepos = []
issue_num = 36606
keywords = []
message_count = 1.0
messages = ['339988']
nosy_count = 6.0
nosy_names = ['ncoghlan', 'nedbat', 'benjamin.peterson', 'michael.foord', 'eric.snow', 'xtreak']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue36606'
versions = ['Python 3.8']